This invention is concerned generally with crop roll forming machines. Specifically it is concerned with such apparatus which improve the core formation of crop material rolls and collect crop material particles lost from the crop package or loose crop material during the roll formation process and recycle those particles back into the roll forming region for inclusion within the completed roll package.
Historically it has been the custom to harvest forage crops by mowing the crops, letting them dry in the field, forming the dried crop material into windrows and passing a hay-baling machine over and along those windrows to form the crop material into rectangular bales. Recent practice has shown that the formation of crop materials into large compact rolls, rather than rectangular bales as formerly done, permitted the crop material to be deposited in roll form and left in fields for extended periods of time since the rolled material tends to provide a self-shedding protective covering from inclement weather. The ability to leave these rolled bales in fields thus obviated the additional steps of gathering the rectangular bales and transporting them to a storage area protected from the elements.
Several methods for forming compact rolls of crop material have evolved through the years. In one of these methods, a machine rolls a swath or windrow of crop material along the ground until a roll of desired size is obtained. Examples of machines utilizing this principle are shown in U.S. Pat. No. 3,110,145, dated Nov. 12, 1963. Another similar machine comprises the subject matter of U.S. Pat. No. 3,650,100, dated Mar. 21, 1972. One of the principal difficulties in using this method of forming rolls of crop material is that a certain amount of the material remains upon the ground without being included in the roll. Furthermore, dirt, clods of earth, stones and the like can also be picked up by the roll and included therein. This is undesirable under certain circumstances.
A later, and generally more successful, method of forming crop rolls comprises a machine in which a swath or windrow of material is picked up from the field and directed onto a lower conveyor. This conveyor transports the material to a roll forming region where an upper apron or flight of belts, usually positioned above and adjacent the conveyor, moves in a suitable direction to rotate the crop material with which it contacts. It has been a continuing problem for this type of roll forming machine to obtain an easily started compact roll core. Similarly, the loss of crop particles from this type of machine has been a lingering concern. Variations of this type of crop roll forming machine are illustrated in U.S. Pat. No. 3,859,909 to Mast, dated Jan. 14, 1975 and U.S. Pat. No. 3,722,197 dated Mar. 27, 1973. An improvement of the former type of machine as shown in U.S. Pat. No. 3,866,531 to Todd, dated Feb. 18, 1975, attempted to solve these problems through the use of leaf springs.
The increasing popularity of crop roll forming machines has seen their use broaden from rolling wintering forage for livestock to rolling high protein crops, such as alfalfa, for dairy livestock where the amount of crop material loss is critical. In this latter area especially, interest in the amount of high nutrient crop material lost during roll formation has intensified.
Additionally, crop roll forming machines have been used in a wider range of crop materials, thus presenting varying core formation problems peculiar to each type of crop. Roll forming machines of the type taught in Todd with leaf springs have proven extremely effective in virtually all types of crops. However, minor difficulties have been experienced with some crops that are short and extremely dry and brittle. Since the leaf springs are motionless they occasionally form a dead area where these extremely short, dry, and brittle crops accumulate since the crops are too brittle to withstand being raised through the vertical distance required for them to come to contact with the live, motion-imparting bale forming means. Such brittle crops occasionally will continue to build up until the roll forming machine becomes less efficient. A similar core forming problem can occur in this type of machine when used in loosely packed, low windrows. Such conditions will delay the formation of a core for the rolled crop material since there will be insufficient crop material being fed by the pickup means onto the floor and transported back to the leaf springs to be forced up and over the leaf springs into contact with the live bale forming means. Crop material, in this instance, will remain on the leaf springs until sufficient quantities of material are fed back to force the material up and over the leaf springs into contact with the bale forming means.
The foregoing problems are solved in the design of the machine comprising the present invention by substantially decreasing the amount of crop material lost during the roll formation process and by allowing the usage of the roll forming machine in a wider range of crops, such as corn, maize stubs and hay, with improved core formation.